Eye fixation experiment. Cognitive scientists at the University of Massachusetts designed an experiment to measure x, the number of times a reader’s eye fixated on a single word before moving past that word (Memory and Cognition, Sept. 1997). For this experiment, x was found to have a mean of 1. Suppose one of the readers in the experiment is randomly selected, and assume that x has a Poisson distribution.

a. Find P1x = 02.

b. Find P1x 7 12.

c. Find P1x … 22.